In the U.S.—

In Canada—

• Antibacterial, systemic

Erythromycin and sulfisoxazole (er-ith-roe-MYE-sin and sul-fi-SOX-a-zole) is a combination antibiotic used to treat ear infections in children. It also may be used for other problems as determined by your doctor. It will not work for colds, flu, or other virus infections.

Erythromycin and sulfisoxazole combination is available only with your doctor's prescription, in the following dosage form:

Oral
• Suspension (U.S. and Canada)

In deciding to use a medicine, the risks of taking the medicine must be weighed against the good it will do. This is a decision you and your doctor will make. For erythromycin and sulfisoxazole, the following should be considered:

Allergies—Tell your doctor if you have ever had any unusual or allergic reaction to the erythromycins or sulfa medicines, furosemide (e.g., Lasix) or thiazide diuretics (water pills), oral antidiabetics (diabetes medicine you take by mouth), or glaucoma medicine you take by mouth (for example, acetazolamide [e.g., Diamox], dichlorphenamide [e.g., Daranide], methazolamide [e.g., Neptazane]). Also tell your health care professional if you are allergic to any other substances, such as foods, preservatives, or dyes.

Pregnancy—Studies have not been done in humans with either erythromycins or sulfa medicines. In addition, erythromycins have not been shown to cause birth defects or other problems in humans. However, studies in mice, rats, and rabbits have shown that some sulfa medicines cause birth defects, including cleft palate and bone problems.

Breast-feeding—Erythromycins and sulfa medicines pass into the breast milk. This medicine is not recommended for use during breast-feeding. It may cause liver problems, anemia, and other unwanted effects in nursing babies, especially those with glucose-6-phosphate dehydrogenase (G6PD) deficiency.

Children—This medicine has been tested in children over the age of 2 months and has not been shown to cause different side effects or problems than it does in adults. This medicine should not be given to infants under 2 months of age unless directed by the child's doctor, because it may cause unwanted effects.

Older adults—This medicine is intended for use in children and is not generally used in adult patients.

Other medicines—Although certain medicines should not be used together at all, in other cases two different medicines may be used together even if an interaction might occur. In these cases, your doctor may want to change the dose, or other precautions may be necessary. When you are taking erythromycin and sulfisoxazole, it is especially important that your health care professional know if you are taking any of the following:

• Acetaminophen (e.g., Tylenol) (with long-term, high-dose use) or
• Amiodarone (e.g., Cordarone) or
• Anabolic steroids (nandrolone [e.g., Anabolin], oxandrolone [e.g., Anavar], oxymetholone [e.g., Anadrol], stanozolol [e.g., Winstrol]) or
• Androgens (male hormones) or
• Antithyroid agents (medicine for overactive thyroid) or
• Carbamazepine (e.g., Tegretol) or
• Carmustine (e.g., BiCNU) or
• Chloroquine (e.g., Aralen) or
• Dantrolene (e.g., Dantrium) or
• Daunorubicin (e.g., Cerubidine) or
• Disulfiram (e.g., Antabuse) or
• Divalproex (e.g., Depakote) or
• Estrogens (female hormones) or
• Etretinate (e.g., Tegison) or
• Gold salts (medicine for arthritis) or
• Hydroxychloroquine (e.g., Plaquenil) or
• Mercaptopurine (e.g., Purinethol) or
• Methotrexate (e.g., Mexate, Rheumatrex) or
• Methyldopa (e.g., Aldomet) or
• Naltrexone (e.g., Trexan) (with long-term, high-dose use) or
• Other anti-infectives by mouth or by injection (medicine for infection) or
• Phenothiazines (acetophenazine [e.g., Tindal], chlorpromazine [e.g., Thorazine], fluphenazine [e.g., Prolixin], mesoridazine [e.g., Serentil], perphenazine [e.g., Trilafon], prochlorperazine [e.g., Compazine], promazine [e.g., Sparine], promethazine [e.g., Phenergan], thioridazine [e.g. Mellaril], trifluoperazine [e.g., Stelazine], triflupromazine [e.g., Vesprin], trimeprazine [e.g., Temaril]) or
• Phenytoin (e.g., Dilantin) or
• Plicamycin (e.g., Mithracin) or
• Valproic acid (e.g., Depakene)—Use of erythromycin and sulfisoxazole with any of these medicines may increase the chance of side effects affecting the liver

• Acetohydroxamic acid (e.g., Lithostat) or
• Dapsone or
• Furazolidone (e.g., Furoxone) or
• Nitrofurantoin (e.g., Furadantin) or
• Primaquine or
• Procainamide (e.g., Pronestyl) or
• Quinidine (e.g., Quinidex) or
• Quinine (e.g., Quinamm) or
• Sulfoxone (e.g., Diasone)—Use of erythromycin and sulfisoxazole with these medicines may increase the chance of side effects

• Alfentanil (e.g., Alfenta)—Long-term use of erythromycin and sulfisoxazole may increase the action of alfentanil and increase the chance of side effects

• Aminophylline (e.g., Truphylline) or
• Caffeine (e.g., NoDoz) or
• Oxtriphylline (e.g., Choledyl) or
• Theophylline (e.g., Slo-Phyllin, Theo-Dur)—Use of erythromycin and sulfisoxazole with these medicines may increase the side effects of these medicines

• Astemizole (e.g., Hismanal) or
• Terfenadine (e.g., Seldane)—Use of astemizole or terfenadine with erythromycin and sulfisoxazole may cause heart problems, such as an irregular heartbeat; these medicines should not be used together

• Anticoagulants (blood thinners) or
• Antidiabetics, oral (diabetes medicine you take by mouth) or
• Ethotoin (e.g., Peganone) or
• Mephenytoin (e.g., Mesantoin)—Use of erythromycin and sulfisoxazole with these medicines may increase the effects of these medicines, thereby increasing the chance of side effects

• Chloramphenicol (e.g., Chloromycetin) or
• Clindamycin (e.g., Cleocin) or
• Lincomycin (e.g., Lincocin)—Use of erythromycin and sulfisoxazole with these medicines may decrease the effectiveness of these medicines

• Cyclosporine (e.g., Sandimmune, Neoral)—Use of any of these medicines with erythromycin and sulfisoxazole may increase the side effects of these medicines

• Methenamine (e.g., Mandelamine)—Use of erythromycin and sulfisoxazole with this medicine may, on rare occasion, increase the chance of side effects affecting the kidneys

• Oral contraceptives (birth control pills) containing estrogen—Use of erythromycin and sulfisoxazole with oral contraceptives may decrease the effectiveness of oral contraceptives, increasing the chance of breakthrough bleeding and pregnancy. Also, the use of erythromycin and sulfisoxazole with oral contraceptives containing estrogen may increase the chance of side effects affecting the liver.

• Vitamin K (e.g., AquaMEPHYTON, Synkayvite)—Patients taking erythromycin and sulfisoxazole may have an increased need for vitamin K

• Anemia or other blood problems or
• Glucose-6-phosphate dehydrogenase (G6PD) deficiency—Erythromycin and sulfisoxazole may increase the chance of blood problems

• Heart disease—High doses of erythromycin and sulfisoxazole may increase the chance of side effects in patients with a history of an irregular heartbeat

• Kidney disease or
• Liver disease—Patients with liver or kidney disease may have an increased chance of side effects

• Loss of hearing—High doses of erythromycin and sulfisoxazole may increase the chance for hearing loss in some patients

• Porphyria—Erythromycin and sulfisoxazole may increase the chance of a porphyria attack

Erythromycin and sulfisoxazole combination is best taken with extra amounts of water and may be taken with food. Additional amounts of water should be taken several times every day, unless otherwise directed by your doctor. Drinking extra water will help to prevent some unwanted effects (e.g., kidney stones) of sulfa medicines.

Do not give this medicine to infants under 2 months of age, unless otherwise directed by your doctor. Sulfa medicines may cause liver problems in these infants.

Use a specially marked measuring spoon or other device to measure each dose accurately. The average household teaspoon may not hold the right amount of liquid.

Do not use after the expiration date on the label. The medicine may not work properly after that date. Check with your pharmacist if you have any questions about this.

To help clear up your infection completely, keep taking this medicine for the full time of treatment, even if you begin to feel better after a few days. If you stop taking this medicine too soon, your symptoms may return.

This medicine works best when there is a constant amount in the blood. To help keep the amount constant, do not miss any doses. Also, it is best to take the doses at evenly spaced times, day and night. For example, if you are to take 4 doses a day, the doses should be spaced about 6 hours apart. If this interferes with your sleep or other daily activities, or if you need help in planning the best times to take your medicine, check with your health care professional.

Dosing—

The dose of erythromycin and sulfisoxazole combination will be different for different patients. Follow your doctor's orders or the directions on the label. The following information includes only the average doses of erythromycin and sulfisoxazole combination. If your dose is different, do not change it unless your doctor tells you to do so.

• For oral dosage form (suspension):
  • For infections caused by bacteria:
    • Adults and teenagers—This medicine is used only in children.
    • Children up to 2 months of age—Use is not recommended.
    • Children 2 months of age and older—Dose is based on body weight:
      For the four-times-a-day dosing schedule
      • Children weighing less than 8 kilograms (kg) (under 18 pounds): Dose must be determined by your doctor.
      • Children weighing 8 to 16 kg (18 to 35 pounds): 1/2 teaspoonful (2.5 milliliters [mL]) every six hours for ten days.
      • Children weighing 16 to 24 kg (35 to 53 pounds): 1 teaspoonful (5 mL) every six hours for ten days.
      • Children weighing 24 to 32 kg (53 to 70 pounds): 1 1/2 teaspoonfuls (7.5 mL) every six hours for ten days.
      • Children weighing more than 32 kg (over 70 pounds): 2 teaspoonfuls (10 mL) every six hours for ten days.
      For the three-times-a-day dosing schedule
      • Children weighing less than 6 kg (under 13 pounds): Dose must be determined by your doctor.
      • Children weighing 6 to 12 kg (13 to 26 pounds): 1/2 teaspoonful (2.5 mL) every eight hours for ten days.
      • Children weighing 12 to 18 kg (26 to 40 pounds): 1 teaspoonful (5 mL) every eight hours for ten days.
      • Children weighing 18 to 24 kg (40 to 53 pounds): 1 1/2 teaspoonfuls (7.5 mL) every eight hours for ten days.
      • Children weighing 24 to 30 kg (53 to 66 pounds): 2 teaspoonfuls (10 mL) every eight hours for ten days.
      • Children weighing more than 30 kg (over 66 pounds): 2 1/2 teaspoonfuls (12.5 mL) every eight hours for ten days.

Missed dose—

If you miss a dose of this medicine, take it as soon as possible. This will help to keep a constant amount of medicine in the blood. However, if it is almost time for your next dose, skip the missed dose and go back to your regular dosing schedule. Do not double the dose.

Storage—

To store this medicine:

• Keep out of the reach of children.
• Store away from heat and direct light.
• Store in the refrigerator because heat will cause this medicine to break down. However, keep the medicine from freezing. Follow the directions on the label.
• Do not keep outdated medicine or medicine no longer needed. Be sure that any discarded medicine is out of the reach of children.

It is very important that your doctor check you at regular visits for any blood problems that may be caused by this medicine, especially if you will be taking this medicine for a long time.

If your symptoms do not improve within a few days, or if they become worse, check with your doctor.

Erythromycin and sulfisoxazole may cause your skin to be more sensitive to sunlight than it is normally. Exposure to sunlight, even for brief periods of time, may cause a skin rash, itching, redness or other discoloration of the skin, or a severe sunburn. When you begin taking this medicine:

• Stay out of direct sunlight, especially between the hours of 10:00 a.m. and 3:00 p.m., if possible.
• Wear protective clothing, including a hat. Also, wear sunglasses.
• Apply a sun block product that has a skin protection factor (SPF) of at least 15. Some patients may require a product with a higher SPF number, especially if they have a fair complexion. If you have any questions about this, check with your health care professional.
• Apply a sun block lipstick that has an SPF of at least 15 to protect your lips.
• Do not use a sunlamp or tanning bed or booth.

If you have a severe reaction from the sun, check with your doctor.

Erythromycin and sulfisoxazole combination may cause blood problems. These problems may result in a greater chance of infection, slow healing, and bleeding of the gums. Therefore, you should be careful when using regular toothbrushes, dental floss, and toothpicks. Dental work should be delayed until your blood counts have returned to normal. Check with your medical doctor or dentist if you have any questions about proper oral hygiene (mouth care) during treatment.

Along with its needed effects, a medicine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor immediately if any of the following side effects occur:

• More common
  • Itching;  skin rash 
  
  

• Less common
  • Aching of joints and muscles;  difficulty in swallowing;  nausea or vomiting;  pale skin;  redness, blistering, peeling, or loosening of skin;  skin rash;  sore throat and fever;  stomach pain, severe;  unusual bleeding or bruising;  unusual tiredness or weakness;  yellow eyes or skin 
  
  

• Rare
  • Blood in urine;  dark or amber urine ;  irregular or slow heartbeat;  temporary loss of hearing (with kidney disease and high doses);  lower back pain;  pain or burning while urinating;  pale stools;  recurrent fainting;  severe stomach pain;  swelling of front part of neck 
  
  

In addition to the side effects listed above, check with your doctor as soon as possible if the following side effect occurs:

• More common
  • Increased sensitivity to sunlight 
  
  

Other side effects may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. However, check with your doctor if any of the following side effects continue or are bothersome:

• More common
  • Abdominal or stomach cramping and discomfort;  diarrhea;  headache;  loss of appetite;  nausea or vomiting 
  
  

• Less common
  • Sore mouth or tongue 
  
  

Other side effects not listed above may also occur in some patients. If you notice any other effects, check with your doctor.

Once a medicine has been approved for marketing for a certain use, experience may show that it is also useful for other medical problems. Although this use is not specifically included in product labeling, erythromycin and sulfisoxazole combination is used in certain patients with the following medical condition:

• Sinusitis (sinus infection)

Other than the above information, there is no additional information relating to proper use, precautions, or side effects for this use.